Passage 5.27.10
παῖς μικρὸς ὑπὸ τούτῳ καθήμενος τῷ βοῒ ἐς τὸ κάτω νενευκὼς ἔπαιζεν· ἀνασχὼν δὲ ἐξαίφνης τὴν κεφαλὴν κατεάγη τε αὐτὴν πρὸς τὸν χαλκὸν καὶ ἐκ τοῦ τραύματος ἡμέραις ὕστερον ἀπέθανεν οὐ πολλαῖς. Ἠλεῖοι μὲν δὴ τὸν βοῦν ἅτε αἵματι ἔνοχον ἐβουλεύοντο ἐκκομίσαι τῆς Ἄλτεως· ὁ δὲ σφᾶς ὁ θεὸς ὁ ἐν Δελφοῖς κατὰ χώραν ἐᾶν τὸ ἀνάθημα καθάρσια ἔχρα ἐπʼ αὐτῷ ποιησαμένους, ὁπόσα Ἕλληνες ἐπὶ ἀκουσίῳ φόνῳ νομίζουσιν.
Under this ox, a small boy, seated and leaning downward, was playing; suddenly raising his head, he struck it against the bronze, and from this wound he died not many days afterward. The Eleans, considering the ox defiled with blood-guilt, intended to remove it from the Altis, but the god at Delphi instructed them to leave the dedication in its place and to perform upon it the rites of purification customary among Greeks for involuntary homicide.